Tensile behavior of textile reinforced ultra-high performance concrete

Textile-reinforced ultra-high performance concrete (TR-UHPC) specimens are developed with various high-performance textiles and volume fractions of steel fibers. Experimental and numerical studies are conducted to investigate the tension-stiffening phenomenon of TR-UHPC and synergistic reinforcing mechanisms. The prepared TR-UHPC specimens exhibit pronounced strain-hardening phenomenon with distributed cracks. The tensile strength, post-cracking stiffness, and ductility improve. When the volume fraction of steel fibers increases from 0.5% to 1.5%, the tensile behavior of the TR-UHPC is primarily affected by the bridging mechanism of steel fibers. In contrast, when it further increases to 2.0%, the bonding between the textile and the UHPC matrix govern the tensile behavior of the TR-UHPC. The multiple cracking process continues throughout the test, indicating the effective load transfer mechanisms under high stress level. The evolution of multiple cracking is quantitatively analyzed using digital image correlation (DIC). The prepared TR-UHPC can satisfy the durability requirements on crack width even under high stress. Additionally, a numerical model is established to incorporate the textile’s tensile properties, the stress-crack width relationship of UHPC, and the interfacial bonding between the textile and the UHPC matrix. The modeling results are consistent with the experimental responses. Thus, the method devised herein can provide a practical basis for determining the optimized reinforcement ratios for TR-UHPC.